package com.zgc.controller;

import com.zgc.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;


import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;

import java.io.FileInputStream;
import java.io.IOException;
import java.util.UUID;


@RestController
@RequestMapping("/common")
@Slf4j
public class CommonController {

    @Value("${reggie.path}")
    private String basePath;

    @PostMapping("/upload")
    public R<String> upload(MultipartFile file) {
//file是一个临时文件，需要转存到指定位置，否则本次请求完成后临时文件会删除
        log.info("文件上传成功");
        //1.获取源文件名
        String filename = file.getOriginalFilename();
        //2.获取后缀名
        String suffix= filename.substring(filename.lastIndexOf("."));//1.jpg
        //3.组织新的临时文件
        String fileName =  UUID.randomUUID().toString()+suffix;
        //4.在服务器创建新的文件夹
        //创建一个目录对象
        File dir = new File(basePath);
        //判断当前目录是否存在
        if(!dir.exists()){
        //目录不存在，需要创建
            dir.mkdirs();
        }
        //5.文件实体转换，存到服务器上
        try {
        //将临时文件转存到指定位置
            file.transferTo(new File(basePath + fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }
        return R.success(fileName);
    }
    /**
     * 文件下载
     * @param name
     * @param response
     */
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response){
        try {
//输入流，通过输入流读取文件内容
            FileInputStream fileInputStream = new FileInputStream(new File(basePath +
                    name));
//输出流，通过输出流将文件写回浏览器
            ServletOutputStream outputStream = response.getOutputStream();
            response.setContentType("image/jpeg");
            int len = 0;
            byte[] bytes = new byte[1024];
            while ((len = fileInputStream.read(bytes)) != -1){
                outputStream.write(bytes,0,len);
                outputStream.flush();
            }
//关闭资源
            outputStream.close();
            fileInputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}


